diff --git a/libavformat/avisynth.c b/libavformat/avisynth.c
index 8ba2bdead2..a97d12b6b6 100644
--- a/libavformat/avisynth.c
+++ b/libavformat/avisynth.c
@@ -34,6 +34,7 @@
 /* Platform-specific directives. */
 #ifdef _WIN32
   #include "compat/w32dlfcn.h"
+  #include "libavutil/wchar_filename.h"
   #undef EXTERN_C
   #define AVISYNTH_LIB "avisynth"
 #else
@@ -56,6 +57,7 @@ typedef struct AviSynthLibrary {
 #define AVSC_DECLARE_FUNC(name) name ## _func name
     AVSC_DECLARE_FUNC(avs_bit_blt);
     AVSC_DECLARE_FUNC(avs_clip_get_error);
+    AVSC_DECLARE_FUNC(avs_check_version);
     AVSC_DECLARE_FUNC(avs_create_script_environment);
     AVSC_DECLARE_FUNC(avs_delete_script_environment);
     AVSC_DECLARE_FUNC(avs_get_audio);
@@ -137,6 +139,7 @@ static av_cold int avisynth_load_library(void)
 
     LOAD_AVS_FUNC(avs_bit_blt, 0);
     LOAD_AVS_FUNC(avs_clip_get_error, 0);
+    LOAD_AVS_FUNC(avs_check_version, 0);
     LOAD_AVS_FUNC(avs_create_script_environment, 0);
     LOAD_AVS_FUNC(avs_delete_script_environment, 0);
     LOAD_AVS_FUNC(avs_get_audio, 0);
@@ -807,26 +810,38 @@ static int avisynth_create_stream(AVFormatContext *s)
 static int avisynth_open_file(AVFormatContext *s)
 {
     AviSynthContext *avs = s->priv_data;
-    AVS_Value arg, val;
+    AVS_Value val;
     int ret;
-#ifdef _WIN32
-    char filename_ansi[MAX_PATH * 4];
-    wchar_t filename_wc[MAX_PATH * 4];
-#endif
 
     if (ret = avisynth_context_create(s))
         return ret;
 
+    if (!avs_library.avs_check_version(avs->env, 7)) {
+        AVS_Value args[] = {
+            avs_new_value_string(s->url),
+            avs_new_value_bool(1) // filename is in UTF-8
+        };
+        val = avs_library.avs_invoke(avs->env, "Import",
+                                     avs_new_value_array(args, 2), 0);
+    } else {
+        AVS_Value arg;
 #ifdef _WIN32
-    /* Convert UTF-8 to ANSI code page */
-    MultiByteToWideChar(CP_UTF8, 0, s->url, -1, filename_wc, MAX_PATH * 4);
-    WideCharToMultiByte(CP_THREAD_ACP, 0, filename_wc, -1, filename_ansi,
-                        MAX_PATH * 4, NULL, NULL);
-    arg = avs_new_value_string(filename_ansi);
+        char *filename_ansi;
+        /* Convert UTF-8 to ANSI code page */
+        if (utf8toansi(s->url, &filename_ansi)) {
+            ret = AVERROR_UNKNOWN;
+            goto fail;
+        }
+        arg = avs_new_value_string(filename_ansi);
 #else
-    arg = avs_new_value_string(s->url);
+        arg = avs_new_value_string(s->url);
 #endif
-    val = avs_library.avs_invoke(avs->env, "Import", arg, 0);
+        val = avs_library.avs_invoke(avs->env, "Import", arg, 0);
+#ifdef _WIN32
+        av_free(filename_ansi);
+#endif
+    }
+
     if (avs_is_error(val)) {
         av_log(s, AV_LOG_ERROR, "%s\n", avs_as_error(val));
         ret = AVERROR_UNKNOWN;
diff --git a/libavformat/http.c b/libavformat/http.c
index c8f3f4b6a3..d90117e422 100644
--- a/libavformat/http.c
+++ b/libavformat/http.c
@@ -29,6 +29,7 @@
 #include "libavutil/avassert.h"
 #include "libavutil/avstring.h"
 #include "libavutil/bprint.h"
+#include "libavutil/getenv_utf8.h"
 #include "libavutil/opt.h"
 #include "libavutil/time.h"
 #include "libavutil/parseutils.h"
@@ -198,6 +199,7 @@ void ff_http_init_auth_state(URLContext *dest, const URLContext *src)
 static int http_open_cnx_internal(URLContext *h, AVDictionary **options)
 {
     const char *path, *proxy_path, *lower_proto = "tcp", *local_path;
+    char *env_http_proxy, *env_no_proxy;
     char *hashmark;
     char hostname[1024], hoststr[1024], proto[10];
     char auth[1024], proxyauth[1024] = "";
@@ -211,9 +213,13 @@ static int http_open_cnx_internal(URLContext *h, AVDictionary **options)
                  path1, sizeof(path1), s->location);
     ff_url_join(hoststr, sizeof(hoststr), NULL, NULL, hostname, port, NULL);
 
-    proxy_path = s->http_proxy ? s->http_proxy : getenv("http_proxy");
-    use_proxy  = !ff_http_match_no_proxy(getenv("no_proxy"), hostname) &&
+    env_http_proxy = getenv_utf8("http_proxy");
+    proxy_path = s->http_proxy ? s->http_proxy : env_http_proxy;
+
+    env_no_proxy = getenv_utf8("no_proxy");
+    use_proxy  = !ff_http_match_no_proxy(env_no_proxy, hostname) &&
                  proxy_path && av_strstart(proxy_path, "http://", NULL);
+    av_freep(&env_no_proxy);
 
     if (!strcmp(proto, "https")) {
         lower_proto = "tls";
@@ -224,7 +230,7 @@ static int http_open_cnx_internal(URLContext *h, AVDictionary **options)
         if (s->http_proxy) {
             err = av_dict_set(options, "http_proxy", s->http_proxy, 0);
             if (err < 0)
-                return err;
+                goto end;
         }
     }
     if (port < 0)
@@ -259,12 +265,12 @@ static int http_open_cnx_internal(URLContext *h, AVDictionary **options)
         err = ffurl_open_whitelist(&s->hd, buf, AVIO_FLAG_READ_WRITE,
                                    &h->interrupt_callback, options,
                                    h->protocol_whitelist, h->protocol_blacklist, h);
-        if (err < 0)
-            return err;
     }
 
-    return http_connect(h, path, local_path, hoststr,
-                        auth, proxyauth);
+end:
+    av_freep(&env_http_proxy);
+    return err < 0 ? err : http_connect(
+        h, path, local_path, hoststr, auth, proxyauth);
 }
 
 static int http_should_reconnect(HTTPContext *s, int err)
diff --git a/libavformat/ipfsgateway.c b/libavformat/ipfsgateway.c
index 83d52293b4..a8323403f0 100644
--- a/libavformat/ipfsgateway.c
+++ b/libavformat/ipfsgateway.c
@@ -20,6 +20,7 @@
  */
 
 #include "libavutil/avstring.h"
+#include "libavutil/getenv_utf8.h"
 #include "libavutil/opt.h"
 #include <sys/stat.h>
 #include "os_support.h"
@@ -55,12 +56,15 @@ static int populate_ipfs_gateway(URLContext *h)
     int stat_ret = 0;
     int ret = AVERROR(EINVAL);
     FILE *gateway_file = NULL;
+    char *env_ipfs_gateway, *env_ipfs_path;
 
     // Test $IPFS_GATEWAY.
-    if (getenv("IPFS_GATEWAY") != NULL) {
-        if (snprintf(c->gateway_buffer, sizeof(c->gateway_buffer), "%s",
-                     getenv("IPFS_GATEWAY"))
-            >= sizeof(c->gateway_buffer)) {
+    env_ipfs_gateway = getenv_utf8("IPFS_GATEWAY");
+    if (env_ipfs_gateway != NULL) {
+        int printed = snprintf(c->gateway_buffer, sizeof(c->gateway_buffer),
+                               "%s", env_ipfs_gateway);
+        av_freep(&env_ipfs_gateway);
+        if (printed >= sizeof(c->gateway_buffer)) {
             av_log(h, AV_LOG_WARNING,
                    "The IPFS_GATEWAY environment variable "
                    "exceeds the maximum length. "
@@ -77,20 +81,25 @@ static int populate_ipfs_gateway(URLContext *h)
 
     // We need to know the IPFS folder to - eventually - read the contents of
     // the "gateway" file which would tell us the gateway to use.
-    if (getenv("IPFS_PATH") == NULL) {
+    env_ipfs_path = getenv_utf8("IPFS_PATH");
+    if (env_ipfs_path == NULL) {
+        char *env_home = getenv_utf8("HOME");
+
         av_log(h, AV_LOG_DEBUG, "$IPFS_PATH is empty.\n");
 
         // Try via the home folder.
-        if (getenv("HOME") == NULL) {
+        if (env_home == NULL) {
             av_log(h, AV_LOG_WARNING, "$HOME appears to be empty.\n");
             ret = AVERROR(EINVAL);
             goto err;
         }
 
         // Verify the composed path fits.
-        if (snprintf(ipfs_full_data_folder, sizeof(ipfs_full_data_folder),
-                     "%s/.ipfs/", getenv("HOME"))
-            >= sizeof(ipfs_full_data_folder)) {
+        int printed = snprintf(
+            ipfs_full_data_folder, sizeof(ipfs_full_data_folder),
+            "%s/.ipfs/", env_home);
+        av_freep(&env_home);
+        if (printed >= sizeof(ipfs_full_data_folder)) {
             av_log(h, AV_LOG_WARNING,
                    "The IPFS data path exceeds the "
                    "max path length (%zu)\n",
@@ -113,9 +122,11 @@ static int populate_ipfs_gateway(URLContext *h)
             goto err;
         }
     } else {
-        if (snprintf(ipfs_full_data_folder, sizeof(ipfs_full_data_folder), "%s",
-                     getenv("IPFS_PATH"))
-            >= sizeof(ipfs_full_data_folder)) {
+        int printed = snprintf(
+            ipfs_full_data_folder, sizeof(ipfs_full_data_folder),
+            "%s", env_ipfs_path);
+        av_freep(&env_ipfs_path);
+        if (printed >= sizeof(ipfs_full_data_folder)) {
             av_log(h, AV_LOG_WARNING,
                    "The IPFS_PATH environment variable "
                    "exceeds the maximum length. "
diff --git a/libavformat/tls.c b/libavformat/tls.c
index 302c0f8d59..ea68f18d3a 100644
--- a/libavformat/tls.c
+++ b/libavformat/tls.c
@@ -26,6 +26,7 @@
 #include "url.h"
 #include "tls.h"
 #include "libavutil/avstring.h"
+#include "libavutil/getenv_utf8.h"
 #include "libavutil/opt.h"
 #include "libavutil/parseutils.h"
 
@@ -60,6 +61,7 @@ int ff_tls_open_underlying(TLSShared *c, URLContext *parent, const char *uri, AV
     char buf[200], opts[50] = "";
     struct addrinfo hints = { 0 }, *ai = NULL;
     const char *proxy_path;
+    char *env_http_proxy, *env_no_proxy;
     int use_proxy;
 
     set_options(c, uri);
@@ -89,9 +91,13 @@ int ff_tls_open_underlying(TLSShared *c, URLContext *parent, const char *uri, AV
     if (!c->host && !(c->host = av_strdup(c->underlying_host)))
         return AVERROR(ENOMEM);
 
-    proxy_path = c->http_proxy ? c->http_proxy : getenv("http_proxy");
-    use_proxy = !ff_http_match_no_proxy(getenv("no_proxy"), c->underlying_host) &&
+    env_http_proxy = getenv_utf8("http_proxy");
+    proxy_path = c->http_proxy ? c->http_proxy : env_http_proxy;
+
+    env_no_proxy = getenv_utf8("no_proxy");
+    use_proxy = !ff_http_match_no_proxy(env_no_proxy, c->underlying_host) &&
                 proxy_path && av_strstart(proxy_path, "http://", NULL);
+    av_freep(&env_no_proxy);
 
     if (use_proxy) {
         char proxy_host[200], proxy_auth[200], dest[200];
@@ -104,6 +110,7 @@ int ff_tls_open_underlying(TLSShared *c, URLContext *parent, const char *uri, AV
                     proxy_port, "/%s", dest);
     }
 
+    av_freep(&env_http_proxy);
     return ffurl_open_whitelist(&c->tcp, buf, AVIO_FLAG_READ_WRITE,
                                 &parent->interrupt_callback, options,
                                 parent->protocol_whitelist, parent->protocol_blacklist, parent);
